Help! Hi channel input JCM800 cuts in and out
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Help! Hi channel input JCM800 cuts in and out
hi guys, 1st post.
as the title says i am having difficulty diagnosing a problem with my 84 JCM800:
the low input works fine with both the master and pre sweeping perfectly . i plug into the hi input and the amp cuts in and out randomly,seems just like a dirty master pot but i don't understand why the low input works fine???...any help appreciated.
as the title says i am having difficulty diagnosing a problem with my 84 JCM800:
the low input works fine with both the master and pre sweeping perfectly . i plug into the hi input and the amp cuts in and out randomly,seems just like a dirty master pot but i don't understand why the low input works fine???...any help appreciated.
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The low input works fine because the high input routes the signal through an extra stage of gain that it doesn't go through when plugged into the low input.
Try replacing the preamp tube. One side of the first preamp tube might be going bad. Also, do what George mentioned above as well. It's something in the very first gain stage so it shouldn't take much to get the high input rockin' again.
Jon
Try replacing the preamp tube. One side of the first preamp tube might be going bad. Also, do what George mentioned above as well. It's something in the very first gain stage so it shouldn't take much to get the high input rockin' again.
Jon
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Try replacing the low input jack. When there's nothing plugged into the low input, the high input gain stage gets coupled to the rest of the amp through the switch contact on the low input making contact with the low input's "tip" connection.
Jon
Jon
There's just that fine line between stupid and clever - Nigel Tufnel
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If ANYTHING is plugged into the Low input, the High input is disconnected. This is because the extra gain stage on the High input connects to the rest of the amp through the switch contact on the Low input jack. When you plug into the Low input jack, you break the connection between the High input gain stage and the rest of the amp. So it would be the same as connecting into the Low input jack.
Jon
Jon
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What the hell is that? Looks like you're trying to say that after smoking two joints JF licks your sack........but the only thing I can say in French is "fuck you" anyway.......won't get me far overseas.Je fume deux joints pendant que JF liches mon sac
I am far more adept at swearing in German, and not just because of the translation in Zappa's liner notes on the song "Stick It Out."

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